But when I look at the data, it’s clear to me that if I entered the race, I could not win. I believe I could win a number of diverse states -- but not enough to win the 270 Electoral College votes necessary to win the presidency.

In a three-way race, it’s unlikely any candidate would win a majority of electoral votes, and then the power to choose the president would be taken out of the hands of the American people and thrown to Congress. The fact is, even if I were to receive the most popular votes and the most electoral votes, victory would be highly unlikely, because most members of Congress would vote for their party’s nominee. Party loyalists in Congress -- not the American people or the Electoral College -- would determine the next president.

As the race stands now, with Republicans in charge of both Houses, there is a good chance that my candidacy could lead to the election of Donald Trump or Senator Ted Cruz. That is not a risk I can take in good conscience.

I have known Mr. Trump casually for many years, and we have always been on friendly terms. I even agreed to appear on “The Apprentice” -- twice. But he has run the most divisive and demagogic presidential campaign I can remember, preying on people’s prejudices and fears. Abraham Lincoln, the father of the Republican Party, appealed to our “better angels.” Trump appeals to our worst impulses.

David Fuller's view

I cannot fault Michael Bloomberg’s logic in this analysis.  His campaign would be interesting but it would also increase the odds of Donald Trump or even possibly Ted Cruz becoming president. 

As a social liberal and fiscal conservative, Bloomberg was my preferred candidate, and he has a better business brain than anyone who has been in this election cycle’s current race.  The US economy looks sort of OK in a troubled neighbourhood but it is not firing on all cylinders.  Its big advantage is a robust system which develops and attracts talent from around the world.  This has enabled the US to increase its lead in the crucially important field of technological innovation.